使用导航组件在片段内加载片段

Question

在家庭片段中，我将 xml 作为

 <androidx.constraintlayout.widget.ConstraintLayout
            android:background="@color/white"
            android:layout_width="match_parent"
            android:layout_height="match_parent">

        <androidx.fragment.app.FragmentContainerView
            android:id="@+id/fragment"
            android:name="androidx.navigation.fragment.NavHostFragment"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            app:defaultNavHost="true"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintHorizontal_bias="0.5"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintBottom_toTopOf="@+id/bottomNavi"
            app:navGraph="@navigation/bottm_navi" />

        <meow.bottomnavigation.MeowBottomNavigation
            android:id="@+id/bottomNavi"
            app:mbn_circleColor="@color/white"
            app:mbn_backgroundBottomColor="@color/app_dark_blue"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent" />
    </androidx.constraintlayout.widget.ConstraintLayout>

我的底部导航是

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/bottm_navi"
    app:startDestination="@id/homeBottomOneFragment">

    <fragment
        android:id="@+id/homeBottomOneFragment"
        android:name="com.krassier.customer.ui.home.bottom.HomeBottomOneFragment"
        android:label="fragment_home_bottom_one"
        tools:layout="@layout/fragment_home_bottom_one" />
    <fragment
        android:id="@+id/homeBottomTwoFragment"
        android:name="com.krassier.customer.ui.home.bottom.HomeBottomTwoFragment"
        android:label="fragment_home_bottom_two"
        tools:layout="@layout/fragment_home_bottom_two" />
    <fragment
        android:id="@+id/homeBottomFourFragment"
        android:name="com.krassier.customer.ui.home.bottom.HomeBottomFourFragment"
        android:label="fragment_home_bottom_four"
        tools:layout="@layout/fragment_home_bottom_four" />
    <fragment
        android:id="@+id/homeBottomThreeFragment"
        android:name="com.krassier.customer.ui.home.bottom.HomeBottomThreeFragment"
        android:label="fragment_home_bottom_three"
        tools:layout="@layout/fragment_home_bottom_three" />
    <fragment
        android:id="@+id/homeFragment2"
        android:name="com.krassier.customer.ui.home.HomeFragment"
        android:label="HomeFragment" >
        <action
            android:id="@+id/action_homeFragment2_to_homeBottomOneFragment"
            app:destination="@id/homeBottomOneFragment" />
        <action
            android:id="@+id/action_homeFragment2_to_homeBottomTwoFragment"
            app:destination="@id/homeBottomTwoFragment" />
        <action
            android:id="@+id/action_homeFragment2_to_homeBottomThreeFragment"
            app:destination="@id/homeBottomThreeFragment" />
        <action
            android:id="@+id/action_homeFragment2_to_homeBottomFourFragment"
            app:destination="@id/homeBottomFourFragment" />
    </fragment>
</navigation>

在我写的homefragment中

 findNavController().navigate(R.id.action_homeFragment2_to_homeBottomOneFragment)

当我点击底部导航时，我试图在 homefragment 中加载另一个片段，因为底部导航在 home 片段中，但错误是

java.lang.IllegalArgumentException：导航操作/目的地 com.krassier.customer:id/action_homeFragment2_to_homeBottomOneFragment 无法从当前目的地 Destination(com.krassier.customer:id/homeFragment) label=fragment_home class=com.krassier。 customer.ui.home.HomeFragment

Answer 1

最后我还是按照常规方式

private fun replaceFragment(fragment: Fragment) {
        val fragmentManager = activity?.supportFragmentManager
        val fragmentTransaction = fragmentManager?.beginTransaction()
        fragmentTransaction?.replace(R.id.homeFragmentContainer, fragment)
        fragmentTransaction?.commit()
    }

Answer 2

既然你在一个片段中，你应该试着用这种方式找到导航控制器。

        val navHostFragment = supportFragmentManager.findFragmentById(R.id. fragment) as NavHostFragment. // the id of your FragmentContainerView
        navController = navHostFragment.navController

您应该利用 NavigationUI 库并让它为您处理导航片段更改逻辑

        binding.bottomNavi.setupWithNavController(navController)

Answer 3

你可以试试这个：

    currentDestination?.getAction(direction.actionId)?.run { navigate(direction) }
}

fun NavController.safeNavigate(
    @IdRes currentDestinationId: Int,
    @IdRes id: Int,
    args: Bundle? = null
) {
    if (currentDestinationId == currentDestination?.id) {
        navigate(id, args)
    }
}

当您多次调用导航方法时会发生此崩溃。

https://nezspencer.medium.com/navigation-components-a-fix-for-navigation-action-cannot-be-found-in-the-current-destination-95b63e16152e